Optical coherence tomography (OCT) is an optical signal acquisition and processing method. OCT can capture micrometer-resolution, three-dimensional images from within optical scattering media (e.g., biological tissue). Optical coherence tomography is an interferometric technique, typically employing near-infrared light. The use of relatively long wavelength light allows it to penetrate into the scattering medium. Depending on the properties of the light, OCT can achieve sub-micron resolution.
Most conventional OCT systems use non-polarization-maintaining (PM) single-mode fiber interconnections and operate by measuring the depth-resolved reflectivity profile of backscattered light. Such non-PM OCT systems are generally inexpensive, allow for easy alignment and handling, and enable flexible sample arm designs which are important for in vivo measurements, such as surgical and endoscopic applications. Polarization-sensitive OCT (PS-OCT) systems have been developed to detect the polarization states reflected from the different depths of tissue by controlling the polarization state of light incident upon the sample.